The html presentation you see right now.
The website we use for the workshop.
Website with R exercises from our statistics courses.
OSF repository with all materials.
For more (professional) examples, see the official Quarto Gallery.
Quarto is relatively new and some things might still be more convenient with R Markdown, but this seems to change rapidly.
Although R Markdown is not going away, new features will probably only be implemented in Quarto.
We suggest to use Quarto instead of R Markdown for new projects, unless you know that some functionality you need is currently not yet available.